How ___ I help them to understand when they won’t listen to me?
A．can B．would C．may D．must
In summer, food will go bad if________in room temperature.
A．leaving B．left C．being left D．having left
QQ, you can chat with your friends, makes communication easy.
A．why B．which C．that D．where
Mike must be angry with me, for he walked me without even saying hello.
A．past B．on C．at D．over
_____ you don’t lose heart, I’m sure you can pass the coming examination.
A. Unless B. As long as C. If not D. Although
My house is the one with a red roof on the street. It ____ and you can find it easily.
A. stands up B. looks out C. sticks out D. wipes out
